In this project, Dr Hui Hong at Creighton University aims to understand the role of the ‘efferent system’ – when the brain communicates with the inner ear about dangerous sound volumes – in hearing loss and tinnitus.
Project start date: June 2026
Project end date: June 2029
About the project
Hearing loss is often associated with tinnitus, the perception of phantom sound. Most research on hearing loss and tinnitus has focused on the sensory route of sound travelling from the ear to the brain. However, hearing also involves a lesser-known feedback system, called the auditory efferent system, which sends signals from the brain back to the ear. This system plays a protective role for the inner ear.
We don’t know how the efferent system contributes to hearing loss and tinnitus. Dr Hui Hong’s team will focus on the ‘lateral olivocochlear (LOC) neurons’, which help the brain to communicate with the inner ear to understand how their function changes after noise-induced hearing loss, and whether these changes influence the development of tinnitus.
How it works
The researchers will use a cutting-edge technique called Patch-seq, to measure the electrical activity and the ‘gene expression’(if the gene is ‘on’ or ‘off’) of individual LOC neurons. This will help them understand how LOC neurons respond to loud noise and what molecular changes underlie those responses. They will compare different levels of noise damage and the different severity in hearing loss they cause.
As hearing loss is closely associated with tinnitus, the researchers will use mice that lack the LOC system to determine whether the absence of this feedback system increases the likelihood of developing tinnitus after loud noise.
What will this research achieve?
The results from this project could have significant implications for treatment. Current options, hearing aids and cochlear implants, are designed to restore sound perception, but do not address the changes in the brain-to-ear feedback system caused by hearing loss. By identifying molecular targets within the LOC system, this study could lay the foundation for developing new drugs or gene therapies to complement existing devices.
About the researcher
Dr Hui Hong is Assistant Professor at Biomedical Sciences and Bellucci Translational Hearing Centre of Creighton University in the United States, and was awarded the Discovery Research Grant.
Several members of my family have experienced age-related hearing loss, and I live with tinnitus that worsens under stress. I have seen how hearing loss can affect communication, overall wellbeing and cognitive function. These personal experiences drive my commitment to advancing hearing research and developing better strategies to improve outcomes for individuals with hearing loss and tinnitus.”
